水库运用对金沙江下游水沙变化的影响  

The impact of reservoir operation on runoff and sediment load change in the lower Jinsha River

作　　者：张国帅 邓安军[1,2] 张帮稳 冯志毅 吕瑞茹 Zhang Guoshuai;Deng Anjun;Zhang Bangwen;Feng Zhiyi;&Lv Ruiru(State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China,Institute of Water Resources and Hydropower Research,Beijing 100048,P.R.China;Key Laboratory of Sediment Science and Northern River Training,Ministry of Water Resources,China Institute of Water Resources and Hydropower Research,Beijing 100048,P.R.China)

机构地区：[1]中国水利水电科学研究院,流域水循环模拟与调控国家重点实验室,北京100048 [2]中国水利水电科学研究院,水利部泥沙科学与北方河流治理重点实验室,北京100048

出　　处：《湖泊科学》2024年第6期1911-1921,共11页Journal of Lake Sciences

基　　金：国家自然科学基金项目(U2040217,U2243237);中国水利水电科学研究院科研专项(WH0145B042021)联合资助。

摘　　要：大型水库运用后,金沙江下游水沙时空分布发生重大变化。本文基于金沙江下游干支流水沙观测资料,分析了下游流域水沙时空分布特性。1954-2021年,金沙江下游径流主要来源为金沙江中游及雅砻江,两者年均径流量为1150.73亿m^(3),占总来水量的80.75%;年输沙量主要来自下游区间,其年均来沙量为9943.17万t,占总输沙量的48.12%。运用Mann-Kendall突变检验、R/S分析以及双累积曲线法,分析水库运用对金沙江下游水沙变化趋势的影响。结果表明:1954-2021年金沙江下游水库运用对年径流量变化趋势无明显影响,而对流域年输沙量影响显著。金沙江下游出口水沙关系在1998、2010及2012年发生突变,主要原因为雅砻江、金沙江中游、下游干流上大型水库的拦沙运用,导致下游出口含沙量由1.82 kg/m^(3)逐步降低为1.31、0.86、0.01 kg/m^(3)。利用金沙江下游干支流水沙关系及沙量平衡原理,分别计算局部区间水库拦沙对流域总减沙量的贡献度。1998-2009年二滩水电站建成运行,金沙江下游出口总减沙率为35.16%,雅砻江水库拦沙对下游总减沙贡献度为32.88%;2010-2012年金安桥等中游水电站运行后,下游出口总减沙率为51.43%,金沙江中游、雅砻江、三堆子至白鹤滩区间和白鹤滩至向家坝区间对下游总减沙贡献度分别为21.54%、23.10%、30.67%、24.69%;2013-2021年金沙江下游梯级水库运行后,下游出口总减沙率为99.37%,4个区间对来沙量减少的贡献度分别为19.64%、14.72%、12.34%、53.30%。The construction and operation of large reservoirs in the main and tributaries generally cause significant changes in the flow and sediment characteristics of the downstream river.Based on the observation data of flow and sediment in the lower reach of the Jinsha River(LJR)from 1954 to 2021,the spatio-temporal variation characteristics of flow and sediment sources in the lower reaches were illuminated.The impact of reservoir operation on flow and sediment variation was analyzed using Mann-Kendall mutation test,R/S analysis,and double cumulative curve.By utilizing the relationship among flow,sediment flow and the principle of sediment balance,the contribution of sediment retention by reservoirs in different reaches to the total sediment reduction in the basin was also revealed.The results showed that 80.75%of the runoff and 51.88%of the sediment in LJR come from its middle reach(MJR)and the Yalong River(YR),indicating certain characteristics of flow and sediment heterogeneity.The sediment retention effect of large reservoirs on YR,MJR and LJR had no remarkable impact on the annual runoff variation at the outlet section,but had a significant impact on sediment transport.The relationship curve of flow and sediment at the outlet section of LJR experienced a downward mutation in 1998,2010 and 2012,with the sediment concentration decreasing from 1.82 kg/m^(3)before 1998 to 1.31 kg/m^(3),0.86 kg/m^(3)and 0.01 kg/m^(3),respectively.The total sediment reduction rate at the outlet of LJR was 35.16%from 1998 to 2009,and the contribution of the Ertan Hydropower Station in YR to the downstream sediment reduction was 32.88%.From^(2)010 to 2012,the total sediment reduction rate at the outlet of LJR after the operation of hydropower stations such as Jin'anqiao in MJR was 51.43%,the contributions of reservoir sediment retention in MJR,YR,reaches from Sanduizi to Baihetan and Baihetan to Xiangjiaba in LJR to the total sediment reduction were 21.54%,23.10%,30.67%and 24.69%,respectively.After the operation of cascade reservoirs in L

关 键 词：金沙江下游 水沙变化趋势 水沙关系 减沙贡献度 

分 类 号：TV697[水利工程—水利水电工程] P333[天文地球—水文科学]